Various electrical devices, including modern computer systems, such as servers, workstations and personal computers, have card components. For example, servers and other computer systems include cards that comply with the Peripheral Component Interconnect (PCI) bus specification, the latest version of which is "PCI Local Bus Specification, Revision 2.1", set forth by the PCI Special Interest Group (SIG) on Jun. 1, 1995. Hereinafter, such cards in compliance with the PCI bus specification (that can be electrically connected to PCI busses complying with the PCI bus specification) are called PCI compliant cards.
In the past, in order to service PCI compliant cards of a server (e.g., add a PCI compliant card, remove a PCI compliant card, or substitute another PCI compliant card for the PCI compliant card, of the server), all operations of the server were shut down, for example, by totally cutting off external electrical power to the server. However, shutting down the entire server caused severe problems. For example, the downtime occurring upon shutting down the server reduced business efficiency and thus increased business costs.
Recently, developments have been made in connection with servers having hot pluggable PCI compliant cards (servers which need not be totally shut down, but instead only having power partially interrupted, only to the specific PCI compliant card serviced). In one proposed system, rocker switches are individually used at the location of each PCI compliant card. For example, when the rocker switch is rotated to rest on top of a PCI compliant card in place in the bay of the server for holding the PCI compliant card, the switch is closed such that power is supplied to the card. When it is desired to service (for example, remove) the card, the rocker switch is rotated to a position in which it does not overlie the PCI compliant card. In this position, in which the card is free of the rocker switch, the rocker switch is open so as to cut off supply of power to the PCI compliant card, while power is still supplied to the remainder of the server (including other PCI compliant cards of the server), and the card can be removed.
However, this technique utilizing the rocker switch has disadvantages. For one thing, it can only be used with servers where the PCI compliant card is insertable/removable via the top of the device. More particularly, the rocker switch technique cannot be utilized in systems where the PCI compliant card is insertable/removable from the rear of the server. Moreover, the rocker switch does not exert sufficient immobilizing force to maintain a stable positioning of the PCI compliant card in the bay of the server for holding the PCI compliant card; that is, in systems utilizing the rocker switch a card holder is required at the rear end of the card (i.e., the end of the card opposite the card end having the support bracket), to stabilize the card in the bay of the server for holding the card.